M2M (Machine to Machine) refers to all technologies and means to establish a connection between machines. The M2M concept appeared in the last century ninety's, but it only stayed in the theoretical stage. After 2000, with the development of mobile communication technology, using the mobile communication technology to achieve networking of machines becomes possible. The M2M service appeared on the market around 2002, and following a rapid development in the subsequent years, it became the focus of many communication equipment providers and telecom carriers. Currently the number of machines around the world is much more than the number of people, good market prospects of M2M technology, therefore, can be foreseen.
The study on M2M communication application scenarios indicates that providing the M2M communication in the mobile network has a promising market prospect. But the M2M service raised a lot of new requirements on the system, and in order to enhance competitiveness of the mobile network in this aspect, it is necessary to optimize the existing mobile network to more effectively support the M2M communication.
Related mobile communication networks are mainly designed for man-to-man communications, but they are not optimized enough for machine-to-machine communications or man-to-machine communications. Furthermore, how the carriers can offer the M2M communication service at a low cost is also the key to the success of M2M communication deployment.
Based on the above situation, it is necessary to study solutions for a mobile network supporting the M2M communication, and the solutions should maximize the reuse of existing networks, reduce the impact of a large number of M2M communications on the network as well as the complexity of operation and maintenance.
Currently, the telecom market is increasingly competitive, the tariffs are declining, and the carriers' profit margins continue to decrease, and the people-based communication market is being saturated, and the M2M is a totally new development opportunity for the carriers.
In order to effectively utilize the mobile network resources, the 3rd Generation Partnership Project (referred to as 3GPP) proposes machine type communication (called MTC), namely Machine-to-Machine and Machine-to-Man communication services, and its service scope is far beyond the previous Human-to-Human (referred to as H2H) communication, and the MTC is very different from the current H2H communication mode in aspects of access control, billing, security, quality of service (referred to as QoS), and service modes and so on.
The architecture of 3GPP Evolved Packet System (referred to as EPS) is shown in FIG. 1, and it can be seen from FIG. 1 that the EPS comprises a radio access network and a core network, wherein the radio access network, for example, comprises UTRAN (Universal Terrestrial Radio Access Network), E-UTRAN (Evolved UTRAN) and GERAN (GSM/EDGE Radio Access Network); the core network, for example, comprises network elements such as MME (Mobility Management Entity), S-GW (Serving Gateway) and P-GW (Packet Data Network Gateway, referred to as PDN gateway) in the EPC (Evolved Packet Core), and it comprises network elements such as SGSN (Serving GPRS Support Node) in the GPRS (General Packet Radio Service) core network; and it comprises the eNB (evolved Node B) in the E-UTRAN.
For a battery-powered MTC UE (User Equipment), measures need to be taken to reduce power consumption of the UE, and for a MTC UE with the power supply, the power consumption of the UE also needs to be reduced in order to achieve the goal of green power-saving. Currently, with the increasing popularity of intelligent phones, there are a large number of applications running on intelligent phones, and these applications may increase battery power consumption of the intelligent phones and shortened the battery life, therefore the power-saving of an intelligent phone is a key issue must to be addressed.
In the Access Stratum (called AS), a LTE (Long Term Evolution) UE has two RRC (Radio Resource Control) states: RRC Idle and RRC Connected, referred to as idle state and connected state; in the non-access stratum (referred to as NAS), the LTE UE has three states: LTE Detached, LTE Idle and LTE Active, wherein the LTE Idle and the LTE Active respectively correspond to the RRC Idle and the RRC Connected, and the LTE Detached refers to the state that the UE is just started up, at this time there is no context of the UE and location of the UE is an unknown at the network side. When sending data, the UE needs to enter into the connected state, and when receiving data, the UE needs to be in the idle state or the connected state, and the UE in the LTE Detached cannot send or receive data. The correspondence between the AS state and the NAS state of the LTE UE is shown in FIG. 2, wherein the LTE Detached does not have a corresponding RRC state.
In the research and practice process of the related art, the following problems are found in the related art: both the MTC UE and the intelligent phones have power-saving needs, but for how to find a power saving method from the perspective of the system and how to reduce the signaling interaction between the UE and the network side, etc., there are currently no solutions.